Your opinion should be respected, as long as it is fair and objective to the matter. There seems to be a strong point in fact that people who laided the advantages of NFP so sincerely and openly, ended in claiming they were ignorant at the time. And that technique is not just difficult, but somewhat dangerous to marital stability.
If sacraments are required for NFP to work, then we should share that fact with “people of good faith”. However, Church teaches morality based on natural law, and while nothing is beyond God’s will, it seems reasonable that even atheist can embrace teaching based on his own nature.
